Allow for empty class prefixes in config array.
Allow for empty class prefixes in config array.

productsupcom/GearmanManager,yonglehou/GearmanManager,yonglehou/GearmanManager,lvbaosong/GearmanManager,hhy5861/GearmanManager,brianlmoon/GearmanManager,hechunwen/GearmanManager,productsupcom/GearmanManager,hechunwen/GearmanManager,hhy5861/GearmanManager